Ground effect machine

ABSTRACT

L. A vehicle adapted to translate in proximity to the earth&#39;&#39;s surface having in combination: A. A FAIRED STREAMLINED BODY HAVING A LEADING EDGE AND A TRAILING EDGE, AND BEING DISPOSED ABOUT A CAMBERED MEAN LINE EXTENDING FROM SAID LEADING EDGE TO SAID TRAILING EDGE, THE BOTTOM OF SAID BODY HAVING A SLOPE IN SAID LEADING EDGE NOT EXCEEDING 10* AND FORMING A DIFFUSER SECTION TO PROVIDE A PRESSURE DIFFERENCE BETWEEN UPPER AND LOWER SURFACE OF SAID BODY DURING TRANSLATION OF SAID BODY THEREBY PRODUCING AERODYNAMIC LIFT; B. MEANS ALONG THE SIDES OF SAID BODY AND DEFINING TWO DOWNWARDLY DIRECTED SLOTS TO PRODUCE DOWNWARDLY DIRECTED JETS; AND C. MEANS FOR DELIVERING AIR TO SAID SLOT DEFINING MEANS BOTH DURING HOVERING AND TRANSLATION, TO DISCHARGE AIR THROUGH SAID SLOTS THEREBY PRODUCING DOWNWARDLY EXTENDING AIR JET CURTAINS AT THE SIDES OF SAID BODY AND OF SAID DIFFUSER SECTION PERMITTING LIFT PRODUCING FLOW INTO SAID DIFFUSER SECTION FROM SAID LEADING EDGE AND TO BE DISCHARGED FROM UNDERNEATH SAID TRAILING EDGE.

United States Patent [72] Inventor Scott C. Rethorst 1661 Lombardy Road,Pasadena, Calif. 91 106 [21] Appl. No. 600,657 [22] Filed Dec. 9, 1966[45] Patented Feb.23, 1971 Continuation-impart of application Ser. No.440,665, Mar. 1, 1965, now abandoned, which is a continuation of Ser.No. 839,870, abandoned [54] GROUND EFFECT MACHINE 9 Claims, 7 DrawingFigs.

[52] U.S. Cl 180/120; 180/ 1 29 [51] Int. Cl B60v1/02, B60v 1/14 [50]Field ofSearch 180/7 (FS) [5 6] References Cited UNITED STATES PATENTS3,124,322 3/1964 Cockerell 180/116X 3,213,956 10/1965 Cockerell 180/126219,133 11/1958 Australia Priniary Examiner-A. Harry Levy FOREIGNPATENTS ABSTRACT: I. A vehicle adapted to translate in proximity to theearth's surface having in combination:

a. a faired streamlined body having a leading edge and a trailing edge,and being disposed about a cambered mean line extending from saidleading edge to said trailing edge, the bottom of said body having aslope in said leading edge not exceeding 10 and forming a diffusersection to provide a pressure difference between upper and lower surfaceof said body during translation of said body thereby producingaerodynamic lift;

b. means along the sides of said body and defining two downwardlydirected slots to produce downwardly directed jets; and

. means for delivering air to said slot defining means both GROUNDEFFECT MACHINE This is a continuation application of my application,Ser. No. 440,665, filed Mar. 1, 1965, which, in turn, is a continuationin part application of my application, Ser. No. 839,870, filed Sept. 14,1959. The matter added to the application Ser. No. 440,665 having beencanceled from this specification. US. Pat. applications Ser. Nos.440,665 and 839,870 have been abandoned.

The invention of this application pertains to improvements in groundeffect machines and in particular relates to an improved ground effectmachine which is shaped to provide a diffuser channel on its undersideto develop a sustaining pressure therein from the forward motion of themachine, and which utilizes a single power flow of air to provide bothpropulsion and a screen for the high pressure diffuser channel flow.

An object may be sustained against the force of gravity in a number ofways now known to man, as follows:

1. Centrifugal force. Examples are the satellites which have been placedin orbit about the earth.

2. Buoyancy. Examples are lighter-than-air machines, balloons, andboats.

3. lmparting downward momentum. Conventional aircraft,

helicopters, and hydrofoils obtain a lift force as a reaction to theirimparting downward'momentum to the fluid in which they are sustained orthrough which they are moved. This reaction force is the commonlyaccepted conventional three dimensional aerodynamic lift, which normallyleaves residual dissipative energy in the air. lnternal Stress. The mostcommon example is any structural support, such as a chair or table leg.A pneumatic tire which contains air under pressure is another example.In this case the air in the tire sustains the compression stress, thepressurized air being contained by tension in the tire wall. ln aconventional Ground Effect Machine a volume of air under the machinesimilarly sustains the compression stress caused by the weight of themachine, the pressurized air in this case being contained by a screen orjet of air emitted around the entire periphery. This peripheral curtainof air is forced outward by the ground, and the resulting centrifugalforce in the curtain is balanced by a pressure which is built up andsustained in the air bubble underneath the machine.

An infinite span wing in motion through the air similarly develops apressure stress in the surrounding air, which produces a two-dimensionalaerodynamic lift force as a reaction to the development of downwardmomentum, but without leaving any residual dissipative energy in theair.

Ground Effect Machines are essentially examples of category 4 above, inutilizing the internal stress that may be developed between the machineand the ground. This force may be developed with no expenditure ofenergy, other than that in the curtain of air itself, and this fact isthe advantage obtained by operating the machine in ground proximity.

Conventional Ground Effect Machines thus obtain their lift as theinternal stress developed in the underside pressure bubble through thecentrifugal force of a peripheral jet sealing curtain. in hovering thepressure bubble is essentially static underneath the machine. Intranslation the pressure bubble is essentially carried with the machineas it moves, the curtain jet being deflected aft to provide propulsion,and the front curtain if desired reduced because of the dynamic pressureprovided by stagnation of the oncoming stream against the front of thepressure bubble as it is moved with the machine. Auxiliary propulsion ifdesired may be provided by external propellers or jet engines.

The present invention provides a fundamental improvement over suchconventional Ground Effect Machines by a unique arrangement whereby intranslation the sustaining force for the machine is developed as aninternal stress, not in a pressure bubble carried with the machine, butin an unpowered flow of air under the machine due to the forward motionof the device itself. In this improved machine its shape andparticularly the effective shape of its underside is configured to pro,-

vide a channel for the air to flow, bounded on the top by the machine,on the bottom by the ground, and on the two sides by the pneumaticcurtain.

In the translation regime the front and rear curtains are turned off sothat air can flow through the channel unobstructed. The machine is thenprovided with an effective concave shape of its underside, as determinedby both the con touring and camberline of the body, so that the dynamicpressure of the air flow under the machine is converted to a staticpressure higher than that on the upper side, and in general higher thanatmospheric, thus providing the internal stress between the machine andthe ground which appears as an upward or lifting force to balance theforce of gravity.

Thus the present invention provides a two-phase machine. In the hovering(or slow translation) phase the machine utilizes an annual jetcompletely around the periphery, sealing the pressure bubble under themachine, and dragging this pressure bubble along with it in slowtranslation. It should be noted that the annular jet completely aroundthe periphery is not a requirement for this invention. For the hovering(or slow translation) phase any part of the periphery, for example thefront and rear, can be sealed by flaps, skegs, or fences of any type,but pneumatic curtains are described here merely to demonstratecompatibility with the high speed channel flow regime and to illustratean operable vehicle.

In the high speed translation phase, the front and rear curtains areturned off, and the pressure bubble is discarded. The externalunpowered. air is then allowed to flow unobstructed through theunderside channel provided by the side jets. The fans on board themachine then deliver air only to the side curtains. The internal stressor pressure in the air flowing through the channel in this casedeveloped by the effective shaping of the underside, both by contouringof the underside and/or curvature of the mean body line of the machine(as well as by the other elements of the channel such as the ground andside jets if applicable), and the side jets simply seal this pressure,at the same time providing propulsion by being inclined aft.

This two-phase improved Ground Effect Machine combines 1) all theadvantages of conventional Ground Effect Machines in hovering with (2)greatly improved translational efficiency due to the development of aninternal stress in an unrestricted flow of air under the machine,thereby overcoming the force of gravity without the requirement ofdragging along the sustaining pressure bubble.

In both these operational phases the sustaining force is the internalstress. No residual downward momentum is required to be imparted to theair as in conventional three-dimensional aerodynamic lift, and there isno corresponding dissipative energy required as in conventional reduceddrag. Energy is required to provide the sealing curtain in bothoperational phases. ln translation additional energy is required toovercome profile drag, but no energy is required to develop the liftforce itself as in a conventional aircraft.

The body of this improved machine of the present invention is thusfaired or streamlined in a vertical section on both the upper andunderside in the direction of motion, and provided with a fairly sharpalthough locally rounded leading edge, and a sharp trailing edge as in aconventional wing. This streamlined body is then superimposed on acambered mean line,

thus producing a body shape having an effective camber or concavecurvature to its underside, which together with its side air curtainsprovides in conjunction with the ground or water surface a channel forthe air flow under the body in such a manner as to provide a liftingforce. In this application, such a body is referred to as a channel flowlifting body. This body thus provides a channel in the streamwisedirection to provide first, a diffuser to slow down and increase thestatic pressure of the air; second to provide a plenum chamber tomaintain this higher pressure under as long a region of the machine aspossible; and third, a contraction region to accelerate the air back toits initial velocity to minimize drag.

These three functional elements of the channel may be provided in' anyone of several ways and yet still accomplish the basic diffusionrequired. For example, the second element, the plenum chamber, may bereduced in size until completely omitted, the channel then consistingsolely of a diffuser section forward, continuing directly into thecontraction section aft. On the other hand, the first element, thediffuser section may be simply reduced in length until finally omittedaltogether, in which case the diffusion will take place externally infront of the machine. Likewise, the last element, the contractionsection, may be also reduced in length until finally omitted altogether,in which case the contraction will take place externally aft of themachine. Or both the diffusion and contraction sections may beaccomplished externally forward and aft of the machine respectively, andthe bottom of the machine itselfthus entirely devoted to the plenumregion, and in this case the bottom of the machine may be flat, theeffective concavity then being provided by the mean line of the bodyitself.

All of these secondary variations nevertheless are subordinate to theprimary feature of a mean camber line which is concave down, thusproviding an effective concavity to the body and its underside smoothlyfrom the leading edge to the trailing edge of the body, therebyproviding aerodynamic lift.

The mass of air flowing through such a diffuser channel must beconserved and hence for incompressible flow the product of the channelcross-sectional area A and the axial velocity V must be constant, wherethe subscript 1 refers to any arbitrary cross section, and where thesubscript 2 refers to any different cross section, i.e.:

Thus, as the channel expands, i.e., as its cross-sectional areaincreases, the axial velocity will decrease. But energy must also beconserved in the flow, and so, as the velocity V decreases, the staticpressure p will increase in accordance with Bernoullis equation, wherepis the density of the fluid, i.e.:

p 4% pV constant This higher static pressure in the channel on theunderside of the machine, as compared to the atmospheric or lowerpressure on its upper surface, provides a force to sustain the machineabove the surface of the ground when in forward motion.

Also, in accordance with the present invention, the edges of the undersurface of the above described body are bounded by a slot through whicha jet is emitted down, thus providing a pneumatic extension of the sidesof the flow channel all the way to the ground, and screening the highpressure air developed therein.

This slot is provided around the entire periphery of the machine, thatis, across the entire front and rear of the underside of the abovedescribed body. However, the sections across the front and rear of thebody are used only when the machine is hovering, as in such cases thejet is required around the entire periphery ofthe machine.

Thus when the machine is hovering, the jet is emitted around the entireperiphery, and is aimed down and inward to provide the greatestcurvature ofthe jet and hence the highest pressure on the underside ofthe machine that may be developed by the centrifugal force of the jet asit is forced to flow outward. The machine may then be moved at moderatespeeds in any direction by suitable deflection of the jet.

For high speed forward translation, the jet is gradually deflected aft,providing propulsion. The jet emitted from the sections of the slotacross the front and rear of the machine are at the same time graduallyshut off, the jet then being emitted only along the sides of the flowchannel. The sustaining pressure is then gradually developed by theforward motion as described above, the jet along the sides screening thehigh pressure air developed in the channel. The flow channel is thenbounded on the top by the machine body, shaped to provide an undersidediffuser as described, on the sides by the jet screen, and on the bottomby the ground or water. The channel aperture at the front of the machineis determined by the height of the machine above the ground, and thewidth between the side jet slots provided. The channel aperture at therear of the machine is similarly determined by the machine height abovethe ground, and the width provided by the side jets in defining thecontraction section. The complete flow perturbation involved in thedevelopment of the lift force underneath the machine, however, mayextend both forward and aft of the machine body itself.

In this specification a pressure bubble is defined as a mass ofpressurized air which is stationary with respect to the vehicle, andthus is dragged along with the vehicle when it moves, and which withrespect to the ground then moves as does the vehicle. On the other hand,the channel flow as described in this specification is not stationarywith respect to the vehicle, but is flowing under the vehicle. Withrespect to the ground, however, the channel flow air is stationary, andthe vehicle moves over it.

An advantage of this novel improved ground effect machine is that athigh speeds it does not have to drag its sustaining bubble along withit, but instead generates a high pressure in the air that it passes overin its channel. This latter mode of operation will require much lesspower than modes of operation which drag a sustaining pressure bubblealong with the machine.

Thus this invention provides a channel shaped, pressure sustained groundeffect machine which will require considerably less power in translationmotion as compared with conventional annular jet machines.

The foregoing and other readily apparent features of my presentinvention will be better understood by reference to the following moredetailed specification and accompanying drawings, in which:

FIG. 1 is a perspective view of the preferred embodiment of a groundeffect machine embodying the features of the present invention, andshowing the machine sustained above water, either hovering or in forwardmotion;

FIG. 2 is an underside perspective view ofthe ground effect machine ofFIG. 1, illustrated as seen from under the water surface;

FIG. 3 is a plan view of the machine of FIG. 1;

FIG. 4 is a side view of the machine of FIG. 1;

FIG. 5 is a front view of the machine of FIG. 1;

FIG. 6 is a sectional view taken along the line 6-6 of FIG. 3,illustrating the inward and downward inclination of the jet to providethe pressure screen, both in hovering and in forward translation motion;and

FIG. 7 is a sectional view taken along the line 7-7 of FIG. 3,illustrating the aft inclination of the jet employed to providepropulsion for forward motion.

In the drawings, like numerals refer to like or corresponding partsthroughout the several views.

Referring to FIG. 1, there is illustrated a ground effect machineconstructed in accordance with the present invention comprising a mainbody, hull, or chassis 20. As illustrated in FIG. 2, this body 20 has onits underside a pressure generating flow channel 21 having a forwarddiffuser section 23, a center plenum chamber 24, and an aft contractionsection 25. The body 20 has a leading edge 33 and trailing edge 34.

The diffuser section 23 is normally limited in its expansion geometry towalls of not more than 10 slope to prevent separation of the air flow.

As illustrated in the side elevation of FIG. 4, the body 20 has acambered mean line 22, with a faired and streamlined thicknessdistribution above and below this line. This body shape, in theproximity of the ground, causes the air flow to diffuse forward and tocontract aft of the machine, such that the stagnation streamline of theair flow forms a continuation of the cambered mean line 22 forward andaft of the body 20 itself.

This extended stagnation streamline 22f forward and 22a aft of themachine extends and bounds the flow channel 21 forward and aft of themachine itself, such that the forward diffuser region 23' extends inpart at least forward of the body 20, and the aft contracting region 25'extends in part at least aft of the body 20.

FIG. 3 further illustrates in a plan view the air flow in the channel 21forward and aft of the body 20, illustrating in particular the curvedstreamlines in the air flow of diffusion in the forward diffuser region23 and of contraction in the aft contracting region 25. g

The entire periphery of the machine 20 is bounded by a slot 27 fromwhich is emitted a jet 28. The air for this jet is taken on board themachine through one or more scoops 29, induced by means such as the airflow device 30, viz. an engine fan combination or a jet engine, whichpumps the air through I a duct or chamber 31 to the slot 27, from whichthe air emerges as the jet 28.

The jet 28 is emitted from the slot 27 around the entire periphery downand inward towards the center of the machine 20, as illustrated in FIG.6, for hovering. For forward motion, the jet 28 is then emitted from thesections of the slot 27 along the sides only, and is deflected aft bypivotable louvers 32, the jet still having a downward component toscreen the sustaining pressure developed in the channel 21 by theforward motion, as illustrated in FIG. 7. Means (not shown) may beprovided to dispose the louvers 32 in such attitude as will provide theproper direction of the jet 28 for any operation condition.

While the preferred form and method of employing the invention have beendescribed and illustrated, it is to be understood that the inventionlends itself to numerous other embodiments without departing from itsbasic principles.

I claim:

l. A vehicle adapted to translate in'proximity to the earth's surfacehaving in combination:

a. a faired streamlined body having a leading edge and a trailing edge,and being disposed about a eambered mean line extending from saidleading edge to said trailing edge, the bottom of said body having aslope in said leading edge not exceeding and forming a diffuser sectionto provide a pressure difference between upper and lower surface of saidbody during translation of said body thereby producing aerodynamiclift;

b. means along the sides of said body and defining two downwardlydirected slots to produce downwardly directed jets; and

c. means for delivering air to said'slot defining means both duringhovering and translation, to discharge air through said slots therebyproducing downwardly extending air jet curtains at the sides of saidbody and of said diffuser section permitting lift producing flow intosaid diffuser section from said leading edge and to be discharged fromunderneath said trailing edge.

2. In the ground effect machine adapted to translate in proximity to theearth's surface, the combination of:

a. a faired streamlined body having a leading edge, a trailing edge, andsides and being disposed about a eambered mean line extending from saidleading edge to said trailing edge, the bottom of said body having aslope in said leading edge not exceeding 10 and forming a diffusersection, said body further having jet producing means including a slotextending around the lower periphery of said body, said slot beingdirected downwardly and inwardly;

b. means for delivering air to said jet producing means both duringhovering and translation;

c. closure means to inhibit air discharge through the portion of theslot which extends along the underside of said leading edge and saidtrailing edge of said body;

. means for operating said closure means to close off said portions ofsaid slot whereby the unpowered air stream to which the body may besubjected when translating relative to the earths surface may developsustaining pressures in combination with said body to provideaerodynamic lift; and

e. thrust control means being disposed in each portion of the slot whichextends along a side of said body, and said thrust control means beingdirectable to vary the direction of the air so emitted through saidportion of the slot to any fore and aft degree whereby a reaction forcein either direction may be imparted to either or both sides of the body.1

3. In a ground effect machine adapted to translate in proximity to theearth 5 surface, the combination of:

a. a faired streamlined body having a leading edge and a trailing edge,and being disposed about a eambered mean line extending from saidleading edge to said trailing edge, the bottom of said body having aslope in said leading edge not exceeding 10 and forming a diffusersection, said body further having jet producing means including a slotextending 'around at least portions of its lower periphery of said body,said .slot being directed downwardly and inwardly; V j

b. means including duct for delivering air to said jet producing meansboth during hovering and translation;

c. closure means governing the portions of the slot which extend alongthe underside'of said leading edge and said trailing edge of said body;

. means for operating said closure-means to close off said portions ofsaid slotfiwhereby the ambient air stream to which the body may besubjected when translating relative to the earths surface may developsustaining pressures in combination with said body to provideaerodynamic lift; and

e. thrust producing means provided in said ground effect machine forproducing translation.

4. A vehicle adapted to translate in proximity to the earth's surfacehaving in combination:

a. a faired streamlined body having a leading edge and a trailing edge,and being disposed about a eambered mean line extending from saidleading edge to said trailing edge, the bottom of said body having aslope in said leading edge not exceeding 10 and forming a diffusersection,

said body further having jet producing means including a slot extendingaround at least portions of its lower periphery of said body, said slotbeing directed downwardly and inwardly;

b. means for delivering air solely to said jet producing means bothduring hovering and translation;

c. closure means being disposed in the slot portions which extend alongthe underside of said leading edge and said trailing edge of said body;

d. means for operating said closure means to close said slot portionsduring translation whereby the exterior air flow to which the body maybe subjected when translating relative to the earths surface may incombination with said body provide aerodynamic lift; and

e. thrust producing means provided in said vehicle for producingtranslation.

5. in a ground effect machine adapted to translate in proximity to theearths surface, the combination of:

a. a faired streamlined body, having a leading edge, a trailing edge,and sides being disposed about a eambered mean line concave downextending from said leading edge to said trailing edge, the bottom ofsaid body having a slope in said leading edge not exceeding 10 and forming a diffuser section, said body further having jet producing meansincluding a slot extending around the lower periphery of said body, saidslot being directed downwardly and inwardly;

b. means for delivering air solely to said jet producing means bothduring hovering and translation;

c. first vane means, said first vane means being disposed in the portionof the slot at said leading edge and at said trailing edge of said body;

(1. means for operating said first vane means to close the slot portionsat said leading and trailing edges whereby the free stream air to whichthe body may be relatively sub jected when translating relative to theearth's surface may develop sustaining pressures in combination withsaid body to provide aerodynamic lift consisting of a lower pressureregion on the upper surface of said body and a higher pressure region onthe lower surface of said body, said sustaining pressure regions beingisolated from each other by side air curtains produced by discharge ofair through slot portions at said sides; and

second vane means, said second vane means being disposed in each portionof the slot which extends along a side of said body, and said secondvane means being directabie to vary the direction of the air so emittedthrough said portion of the slot to any fore and aft degree, whereby areaction force in either direction of a preselected degree may beimparted to either or both sides of the body by a particular dispositionof the direction of the said second vane means in said portion of theslot.

6. In a ground effect machine adapted to translate in proximity to theearths surface, the combination of b. means for delivering air solely tosaid jet producing means both during hovering and translation;

closure means disposed in the portion of the slot which extends alongthe underside of said leading edge and said trailing edge of said body;

. means for operating said closure means to close off said portions ofsaid slot whereby the unpowered air stream to which the body may besubjected when translating relative to the earths surface may developsustaining pressures n combination with said body to provide aerodynamiclift; and

. thrust control means being disposed in each portion of the slot whichextends along a side of said body, and said thrust control means beingdirectable to vary the direction of the air so emitted through saidportion ofthe slot to any fore and aft degree wherebya reaction force ineither direction may be imparted to either or both sides of the body.

7. In a ground effect machine adapted to translate in proximity to theearths surface, the combination of:

a faired streamlined body having a leading edge and a trailing edge, andbeing disposed about a cambered mean line extending from said leadingedge to said trailing edge, the bottom of said body having a slope insaid leading edge not exceeding 10 and forming a diffuser section, saidbody further having jet producing means including a slot extendingaround at least portions of the lower periphery of said body, said slotbeing directed downwardly and inwardly;

b. means for delivering air solely to said jet producing means bothduring hovering and translation;

closure means disposed in each portion of the slot which extends alongthe underside of said leading edge and said trailing edge of said body;

d. means for operating said closure means to close off said portions ofsaid slot, whereby the ambient air stream to which the body may besubjected when translating relative to the earth's surface may developsustaining pressures in combination with said body to provideaerodynamic lift; and

thrust producing means provided in said ground effect machine forproducing translation.

8. In a ground effect machine adapted to translate in proximity to theearths surface, the combinationof:

a. a faired streamlined body having a leading edge, a trailing means fordelivering air to said jet producing means both during hovering andtranslation;

first vane means, said first vane means being disposed in the portion ofthe slot at said leading edge and at said trailing edge of said body;

means for operating said first vane means to close the slot portions atsaid leading and trailing edges whereby the free stream air to which thebody may be relatively subjected when translating relative to the earths surface may develop sustaining pressures in combination with said bodyto provide aerodynamic lift consisting of a lower pressure region on theupper surface of said body and a higher pressure region on the lowersurface of said body, said sustaining pressure regions being isolatedfrom each other by side air curtains produced by discharge of airthrough slot portions at said sides; and

second vane means, said second vane means being disposed in each portionofthe slot which extends along a side of said body, and said second vanemeans being directable to vary the direction of the air so emittedthrough said portion of the slot to any fore and aft degree, whereby areaction force in either direction of a preselected degree may beimparted to either or both sides of the body by a particular dispositionof the direction of the said second vane means in said portion of theslot.

9. A vehicle adapted to translate in proximity to the earths surfacehaving in combination:

a. a faired streamlined body having a leading edge and a trailing edge,and being disposed about a mean line extending from said leading edge tosaid trailing edge, said mean line being cambered concave down along atleast a part of its length, the bottom of said body having a slope insaid leading edge not exceeding 10 and forming a diffuser section, saidbody further having jet producing means including a slot extendingaround at least portions of the lower periphery of said body, and saidslot being directed downwardly and inwardly;

. means for delivering air to said jet producing means both duringhovering and translation;

. closure means to inhibit air discharge through each portion of theslot which extends along the underside of said leading edge and saidtrailing edge of said body;

. means for operating said closure means to close off said portions ofsaid slot, whereby the ambient air stream to which the body may besubjected when translating relative to the earth's surface may developsustaining pressures in combination with said body to provideaerodynamic lift; and

. thrust producing means provided in said vehicle for producingtranslation.

1. A vehicle adapted to translate in proximity to the earth''s surfacehaving in combination: a. a faired streamlined body having a leadingedge and a trailing edge, and being disposed about a cambered meAn lineextending from said leading edge to said trailing edge, the bottom ofsaid body having a slope in said leading edge not exceeding 10* andforming a diffuser section to provide a pressure difference betweenupper and lower surface of said body during translation of said bodythereby producing aerodynamic lift; b. means along the sides of saidbody and defining two downwardly directed slots to produce downwardlydirected jets; and c. means for delivering air to said slot definingmeans both during hovering and translation, to discharge air throughsaid slots thereby producing downwardly extending air jet curtains atthe sides of said body and of said diffuser section permitting liftproducing flow into said diffuser section from said leading edge and tobe discharged from underneath said trailing edge.
 2. In the groundeffect machine adapted to translate in proximity to the earth''ssurface, the combination of: a. a faired streamlined body having aleading edge, a trailing edge, and sides and being disposed about acambered mean line extending from said leading edge to said trailingedge, the bottom of said body having a slope in said leading edge notexceeding 10* and forming a diffuser section, said body further havingjet producing means including a slot extending around the lowerperiphery of said body, said slot being directed downwardly andinwardly; b. means for delivering air to said jet producing means bothduring hovering and translation; c. closure means to inhibit airdischarge through the portion of the slot which extends along theunderside of said leading edge and said trailing edge of said body; d.means for operating said closure means to close off said portions ofsaid slot whereby the unpowered air stream to which the body may besubjected when translating relative to the earth''s surface may developsustaining pressures in combination with said body to provideaerodynamic lift; and e. thrust control means being disposed in eachportion of the slot which extends along a side of said body, and saidthrust control means being directable to vary the direction of the airso emitted through said portion of the slot to any fore and aft degreewhereby a reaction force in either direction may be imparted to eitheror both sides of the body.
 3. In a ground effect machine adapted totranslate in proximity to the earth''s surface, the combination of: a. afaired streamlined body having a leading edge and a trailing edge, andbeing disposed about a cambered mean line extending from said leadingedge to said trailing edge, the bottom of said body having a slope insaid leading edge not exceeding 10* and forming a diffuser section, saidbody further having jet producing means including a slot extendingaround at least portions of its lower periphery of said body, said slotbeing directed downwardly and inwardly; b. means including duct fordelivering air to said jet producing means both during hovering andtranslation; c. closure means governing the portions of the slot whichextend along the underside of said leading edge and said trailing edgeof said body; d. means for operating said closure means to close offsaid portions of said slot, whereby the ambient air stream to which thebody may be subjected when translating relative to the earth''s surfacemay develop sustaining pressures in combination with said body toprovide aerodynamic lift; and e. thrust producing means provided in saidground effect machine for producing translation.
 4. A vehicle adapted totranslate in proximity to the earth''s surface having in combination: a.a faired streamlined body having a leading edge and a trailing edge, andbeing disposed about a cambered mean line extending from said leadingedge to said trailing edge, the bottom of said body having a slope insaid leading edge not exceeding 10* and forming a diffuser section, saidbody further having jet produCing means including a slot extendingaround at least portions of its lower periphery of said body, said slotbeing directed downwardly and inwardly; b. means for delivering airsolely to said jet producing means both during hovering and translation;c. closure means being disposed in the slot portions which extend alongthe underside of said leading edge and said trailing edge of said body;d. means for operating said closure means to close said slot portionsduring translation whereby the exterior air flow to which the body maybe subjected when translating relative to the earth''s surface may incombination with said body provide aerodynamic lift; and e. thrustproducing means provided in said vehicle for producing translation. 5.In a ground effect machine adapted to translate in proximity to theearth''s surface, the combination of: a. a faired streamlined body,having a leading edge, a trailing edge, and sides being disposed about acambered mean line concave down extending from said leading edge to saidtrailing edge, the bottom of said body having a slope in said leadingedge not exceeding 10* and forming a diffuser section, said body furtherhaving jet producing means including a slot extending around the lowerperiphery of said body, said slot being directed downwardly andinwardly; b. means for delivering air solely to said jet producing meansboth during hovering and translation; c. first vane means, said firstvane means being disposed in the portion of the slot at said leadingedge and at said trailing edge of said body; d. means for operating saidfirst vane means to close the slot portions at said leading and trailingedges whereby the free stream air to which the body may be relativelysubjected when translating relative to the earth''s surface may developsustaining pressures in combination with said body to provideaerodynamic lift consisting of a lower pressure region on the uppersurface of said body and a higher pressure region on the lower surfaceof said body, said sustaining pressure regions being isolated from eachother by side air curtains produced by discharge of air through slotportions at said sides; and e. second vane means, said second vane meansbeing disposed in each portion of the slot which extends along a side ofsaid body, and said second vane means being directable to vary thedirection of the air so emitted through said portion of the slot to anyfore and aft degree, whereby a reaction force in either direction of apreselected degree may be imparted to either or both sides of the bodyby a particular disposition of the direction of the said second vanemeans in said portion of the slot.
 6. In a ground effect machine adaptedto translate in proximity to the earth''s surface, the combination of a.a faired streamlined body having a leading edge, a trailing edge, andsides and being disposed about a cambered mean line extending from saidleading edge to said trailing edge, the bottom of said body having aslope in said leading edge not exceeding 10*and forming a diffusersection, said body further having jet producing means including a slotextending around the lower periphery of said body, said slot beingdirected downwardly and inwardly; b. means for delivering air solely tosaid jet producing means both during hovering and translation; c.closure means disposed in the portion of the slot which extends alongthe underside of said leading edge and said trailing edge of said body;d. means for operating said closure means to close off said portions ofsaid slot whereby the unpowered air stream to which the body may besubjected when translating relative to the earth''s surface may developsustaining pressures in combination with said body to provideaerodynamic lift; and e. thrust control means being disposed in eachportion of the slot which extends along a side of said body, and saidthrust control means being directable to vary the directIon of the airso emitted through said portion of the slot to any fore and aft degreewhereby a reaction force in either direction may be imparted to eitheror both sides of the body.
 7. In a ground effect machine adapted totranslate in proximity to the earth''s surface, the combination of: a. afaired streamlined body having a leading edge and a trailing edge, andbeing disposed about a cambered mean line extending from said leadingedge to said trailing edge, the bottom of said body having a slope insaid leading edge not exceeding 10* and forming a diffuser section, saidbody further having jet producing means including a slot extendingaround at least portions of the lower periphery of said body, said slotbeing directed downwardly and inwardly; b. means for delivering airsolely to said jet producing means both during hovering and translation;c. closure means disposed in each portion of the slot which extendsalong the underside of said leading edge and said trailing edge of saidbody; d. means for operating said closure means to close off saidportions of said slot, whereby the ambient air stream to which the bodymay be subjected when translating relative to the earth''s surface maydevelop sustaining pressures in combination with said body to provideaerodynamic lift; and e. thrust producing means provided in said groundeffect machine for producing translation.
 8. In a ground effect machineadapted to translate in proximity to the earth''s surface, thecombination of: a. a faired streamlined body having a leading edge, atrailing edge, and sides being disposed about a mean line being at leastpartially cambered concave down and extending from said leading edge tosaid trailing edge, the bottom of said body having a slope in saidleading edge not exceeding 10* and forming a diffuser section, said bodyfurther having jet producing means including a slot extending around thelower periphery of said body, said slot being directed downwardly andinwardly; b. means for delivering air to said jet producing means bothduring hovering and translation; c. first vane means, said first vanemeans being disposed in the portion of the slot at said leading edge andat said trailing edge of said body; d. means for operating said firstvane means to close the slot portions at said leading and trailing edgeswhereby the free stream air to which the body may be relativelysubjected when translating relative to the earth''s surface may developsustaining pressures in combination with said body to provideaerodynamic lift consisting of a lower pressure region on the uppersurface of said body and a higher pressure region on the lower surfaceof said body, said sustaining pressure regions being isolated from eachother by side air curtains produced by discharge of air through slotportions at said sides; and e. second vane means, said second vane meansbeing disposed in each portion of the slot which extends along a side ofsaid body, and said second vane means being directable to vary thedirection of the air so emitted through said portion of the slot to anyfore and aft degree, whereby a reaction force in either direction of apreselected degree may be imparted to either or both sides of the bodyby a particular disposition of the direction of the said second vanemeans in said portion of the slot.
 9. A vehicle adapted to translate inproximity to the earth''s surface having in combination: a. a fairedstreamlined body having a leading edge and a trailing edge, and beingdisposed about a mean line extending from said leading edge to saidtrailing edge, said mean line being cambered concave down along at leasta part of its length, the bottom of said body having a slope in saidleading edge not exceeding 10* and forming a diffuser section, said bodyfurther having jet producing means including a slot extending around atleast portions of the lower periphery of said body, and said sloT beingdirected downwardly and inwardly; b. means for delivering air to saidjet producing means both during hovering and translation; c. closuremeans to inhibit air discharge through each portion of the slot whichextends along the underside of said leading edge and said trailing edgeof said body; d. means for operating said closure means to close offsaid portions of said slot, whereby the ambient air stream to which thebody may be subjected when translating relative to the earth''s surfacemay develop sustaining pressures in combination with said body toprovide aerodynamic lift; and e. thrust producing means provided in saidvehicle for producing translation.